Fabric Defects
This domain tests defect identification, root causes, mending decisions and the 4-point inspection system used to grade greige and finished fabric.
Core rules
- Warp-way defects include missing end, tight end, loose end, warp float and end-out. Causes include warp breaks, dropper failure and sizing faults.
- Weft-way defects include missing pick, double pick, weft crack, weft float and slub. Causes include weft stop failure, picking faults and poor yarn clearing.
- Both-way and surface defects include holes, oil stains, reed marks, temple marks, selvedge defects and crease marks.
- The 4-point system assigns points by defect length: up to 3 in = 1; over 3 to 6 in = 2; over 6 to 9 in = 3; over 9 in = 4. Holes up to 1 in = 2; over 1 in = 4.
- Points are normally expressed per 100 square yards or per 100 linear yards, so the basis must be stated.
- Mending is economic only when the defect can be repaired without weakening the cloth or changing appearance.
Worked example
A 100-yard roll, 60 in wide, has a 10-in warp float (4 points), a 2-in oil stain (1), a 0.5-in hole (2) and a 5-in weft crack (2). Total = 9 points. Area = 100 × 60 / 36 = 166.67 square yards. Points per 100 square yards = 9 × 100 / 166.67 = 5.4.
Traps
- Scoring a hole by the same length scale as a surface defect.
- Mixing points per 100 linear yards with points per 100 square yards.
- Counting the same defect twice after mending.
- Treating all stains as removable.
- Recording a defect without its location and size.